This invention relates to multiple implement screeds. More particularly, this invention relates to adaptations of such screeds for enhanced loose material grading.
Multiple implement screeds such as those manufactured by Somero Enterprises, Inc., of Houghton, Mich., typically comprise a forward loose material grading plow or blade followed by one or more screeding implements mounted to the rear of the forward grading blade. Typically, the working surfaces of such screeding implements mounted to the rear of such forward grading blade are positioned at successively lower elevations with respect to the lower lip of the forward grading blade. Such arrangements of the forward grading blade and rearwardly installed screeding implements restricts the functionality and usefulness of the forward grading blade. For example, concrete slab floors are commonly poured over a base layer of sand. It is often desirable to level and smooth the base layer of sand prior to pouring of concrete thereover. A loose material grading plow or blade similar to that which is commonly installed as the forward implement of a multi-implement screed, is typically utilized for leveling and smoothing of such base sand layers. However, the relatively high elevation of the lower edge of the grading blade of a multi-implement screed undesirably prevents such blade from being utilized for screeding such base layers of sand.
The instant inventive screed solves such deficiency by providing a second removably attachable grading blade. Provision and attachment of such blade allows a common multi-implement screed to be alternately utilized for sand or other loose material grading.
A primary structural component of the instant inventive multi-implement screed comprises a laterally oblongated implement suspension frame having a first material grading blade fixedly attached to and extending downwardly from its forward end. Considering such first grading blade as being a first screeding implement, a second screeding implement is fixedly attached to the screeding implement suspension frame so that it extends downwardly therefrom, and so that it is positioned rearwardly from the first grading blade. The second screeding implement may consist of any of several commonly known screeding implements such as helical bladed material conveyors, flanged conveyors, flat trowels, vibratory trowels, surface scoring trowels, and rollers. Preferably, the elevation of the lower working surface of the second screeding implement is below the elevation of the first grading blade. Suitably, a third screeding implement selected from the group described above may similarly be installed to the rear of the second screeding element, the elevation of the lower working surface of the third screeding implement preferably being at or below the elevation of the lower working surface of the second screeding implement.
A second material grading blade is necessarily provided, such blade preferably having a vertical dimension such that upon attachment to the lower edge of the first grading blade, the lower edge of the second grading blade extends downwardly to an elevation below the working surfaces of each of the other screeding implements. Removable attaching means are necessarily provided for attaching the second material grading blade to the first material grading blade, such means preferably comprising combinations of spirally threaded bolts or lugs and nuts. Spirally threaded nut and bolt combinations, spirally threaded screws, slip sleeve and slip pin combinations, eye and pin combinations, pin and device combinations, and quick disconnect couplings may be suitably alternately utilized as means for removably attaching the second material grading blade to the first material grading blade.
In use of the present inventive multiple implement screed, the implement may be driven or drawn through an uneven layer of base sand, desirably smoothing and leveling the sand layer in preparation for concrete pouring. Thereafter, concrete may be poured, and the second material grading blade may be removed, allowing the multiple implement screed to smooth and level the concrete.
Accordingly, it is an object of the present invention to provide a multiple implement screed which is capable of alternately functioning independently as a loose material grading blade.